13. Banqiao Dam failure
In August 1975, as a result of the cyclone collision, Typhoon Nina brought heavy rains – 7.46 inches per hour and 41.7 inches daily. Due to an extensive clogging, the dam could no longer perform its role. In just a few days after it erupted, around 16,000 billion tons of water swept over the countryside and killed more than 231,000 people.